Create custom UIs for Wear devices

User interfaces for watch apps differ significantly from user interfaces for
phone apps. Watch apps should follow the guidelines on the
Wear OS by Google design site and implement the UI
patterns on that site, which ensure the following:

Note: We recommend using Android Studio for
Wear OS development, as it provides project setup, library inclusion,
and packaging conveniences. This training assumes you are using
Android Studio.

The Wearable Support Library, which is in the Google Repository in
the Android SDK, provides classes that help you implement UI patterns and
create layouts that work on round and square Wear OS devices.

Note that the following classes in the Wear support library are
deprecated in Wear 2.0: